The present invention relates to a device for gripping a workpiece. In particular, the present invention relates to a device for moving workpiece gripping jaws toward and away from each other.
A device for moving members into engagement with a workpiece is used in robotics and many other types of material handling equipment. It is important in the operation of such a device that the jaws or other workpiece engaging elements move synchronously. It is also important that the device be lightweight and efficient in operation and simple in construction.
A known device for moving members into engagement with a workpiece includes a pair of pistons movable toward and away from each other. The pistons are located in a cylindrical bore of a housing. A rod has a driving interconnection with each of the pistons to ensure synchronous movement of the pistons. The rod is supported by a bearing assembly located in a central portion of the housing. Two fluid pressure chambers are located on opposite sides of the bearing assembly in the housing. Fluid pressure is directed to the fluid pressure chambers to move the pistons away from each other. Fluid pressure chambers at opposite axial ends of the housing receive fluid pressure to move the pistons toward each other.